Seven men who posed as police investigating Al Qaeda terrorists were arrested in a string of violent home invasions that targeted Armenian Americans in the San Fernando Valley, authorities said Thursday. The capture of the men, all undocumented immigrants from El Salvador and Guatemala, was announced by Los Angeles Police Chief William J. Bratton. Detectives believe the men are responsible for at least three home-invasion robberies in the Van Nuys and North Hollywood areas since Jan. 2.

Three robbers, two of them wielding Uzi submachine guns, burst into a house Sunday night and robbed a family of $20,000 worth of silver and gold bars, cash and jewelry, police said. The robbers, two men and a woman, then fled in the victim's car, a blue 1984 Mercury, police said. Details of the 9 p.m. robbery were sketchy Sunday night, but police said no one was hurt at the residence, near Dolphin and Ocean avenues. Police said the woman and her partners barged into the house and demanded money.

Five people were arrested Thursday after tying up a 66-year-old baby-sitter and robbing a house before driving away and crashing into a tree, police said. Police seized three handguns and retrieved an undetermined amount of jewelry and a gun stolen from the home in the 1600 block of West Crone Avenue. Malee Burasombut told police she was ironing when four people charged into the kitchen, bound and gagged her, then robbed the house.

The three suspects planned the robbery meticulously, authorities said. They would abduct a jeweler at gunpoint as he arrived at a Garden Grove home to celebrate Thanksgiving, steal his cash and diamonds and then ransack his relatives' home, officials said. But when the suspects neared their intended target Wednesday evening, a team of law enforcement officers swooped down and quickly took them into custody, a police helicopter hovering overhead. There was no jeweler; the house was vacant.

Police were searching for three men who entered a house, tied up seven members of a family, then escaped with an undetermined amount of valuables, police said. The home-invasion robbery occurred about 7:45 p.m. Monday in the 8000 block of Kiner Avenue, Police Lt. Dan Johnson said. No one was injured, Johnson said. The robbers, two of whom were armed with handguns, entered the house through a closed but unlocked, rear sliding-glass door, Johnson said.

As a homeowner in an upscale Pasadena neighborhood underwent surgery Friday for multiple gunshot wounds, police began the hunt for two men in ski masks who forced their way into his house in the early morning and shot him after he challenged them with a gun. The pair of intruders, both of whom fired handguns, fled the home in the 600 block of Prospect Boulevard near the Rose Bowl after the confrontation about 2 a.m., Pasadena police said.

A parolee from South Los Angeles has been arrested in connection with a series of "hot prowl" break-ins and home-invasion robberies at the Oakwood apartments on Barham Boulevard in the San Fernando Valley, police said Monday. Norris Denton, 27, of Los Angeles and an unidentified 17-year-old accomplice were arrested Saturday afternoon in connection with at least seven crimes reported over the last month at the housing complex near Universal Studios, said Los Angeles Police Lt. Alan Hamilton.